restriction plate
nounA flat piece of metal with a hole in it that controls how much air or liquid can pass through.
The mechanic installed a restriction plate to limit the airflow into the engine.
RELATED WORDS
OTHER MEANINGS
2. A plate in a camera or optical device that narrows the light path to reduce glare or control the field of view.
The telescope's restriction plate blocked stray light from entering the lens.
3. A metal plate placed over a drain or vent to reduce the size of its opening.
A restriction plate on the storm drain keeps large debris from clogging the pipe.
4. In racing, a plate fitted to an intake to limit engine power for fairness or safety.
Officials added a restriction plate to every car to keep speeds competitive.
5. A small plate used in fluid systems to create a deliberate pressure drop.
The engineer measured the pressure across the restriction plate to check the flow rate.